mcp-show-on-kindle

An MCP server with a single tool, show(file_path), which copies a file to a Kindle running KOReader and opens it on the screen.

The Kindle is located on the local network by its KOReader SSH banner, the file is copied over the SSH server plugin, and the running KOReader is told to open it through the HTTP inspector plugin. The inspector is reached over the same SSH connection, so the only thing on the wire is SSH.

Setup on the Kindle

Enable two KOReader plugins on autostart:

• SSH server: port 2222, your public key in /mnt/us/koreader/settings/SSH/authorized_keys
• HTTP inspector: port 8080

The inspector has no authentication, so block it from the network:

ssh -p 2222 root@KINDLE "iptables -I INPUT 1 -p tcp --dport 8080 ! -i lo -j DROP"

Add the same line near the top of /mnt/us/koreader/koreader.sh to apply it on every start.

Setup on the computer

Add to your MCP client config (Claude Desktop, Claude Code, ...):

{
  "mcpServers": {
    "show_on_kindle": {
      "command": "uvx",
      "args": ["--from", "mcp-show-on-kindle==2026.10.09.184938",
               "--refresh-package", "mcp-show-on-kindle", "mcp-show-on-kindle"],
      "env": {
        "KINDLE_ALLOWED_DIRECTORIES": "/some/dir"
      }
    }
  }
}

Or run it as a long-running service with --transport streamable-http --port 7004 and this client config:

{"mcpServers": {"show_on_kindle": {"type": "http", "url": "http://localhost:7004/mcp"}}}

For hacking on a checkout: uv sync, then point the client at "command": "uv", "args": ["run", "--directory", "/path/to/checkout", "mcp-show-on-kindle"].

Configuration

KINDLE_ALLOWED_DIRECTORIES  directories show() may read from. Required.
KINDLE_HOST                 Kindle IP. Default: scan the /24, cache the result.
KINDLE_SSH_PORT             default 2222
KINDLE_HTTP_PORT            default 8080
KINDLE_DIR                  target directory, default /mnt/us/documents/llm
KINDLE_KNOWN_HOSTS          pinned host key, default ~/.config/mcp-show-on-kindle/known_hosts

Security

The banner only locates the Kindle. Authentication is the SSH host key, pinned on first contact under a fixed alias; a different host presenting the same banner fails. File reads are restricted to KINDLE_ALLOWED_DIRECTORIES, and filenames are reduced to [A-Za-z0-9._-] before they are used in a remote command. With the iptables rule in place the Kindle exposes nothing but public-key SSH. Use a separate passphrase-less key that grants access to nothing else.

Tests

make tests-run

ssh and sockets are mocked; the tests run without a Kindle.

My Other LLM Projects

• MCP Alchemy - Connect Claude Desktop to databases for exploring schema and running SQL.
• MCP Redmine - Let Claude Desktop manage your Redmine projects and issues.
• MCP Notmuch Sendmail - Email assistant for Claude Desktop using notmuch.
• Diffpilot - Multi-column git diff viewer with file grouping and tagging.
• Claude Local Files - Access local files in Claude Desktop artifacts.

License

MPL 2.0